Mandibular movement recorder

ABSTRACT

The various styli mounted on a lower U shaped frame for making traces on recording plates mounted on an upper U shaped frame in response to movements of a patient&#39;&#39;s mandible when the lower and upper frames are secured to the patient&#39;&#39;s jaws are arranged to be simultaneously retracted from the recording plates by air pressure. Towards this end, an air pressure source feeds a plurality of tubes having exit openings adjacent to the various styli such that an air stream will simultaneously impinge upon surface areas provided on the styli to effect simultaneous retraction. Inadvertent or spurious traces in retracting the styli as has formerly been done by hand are thus avoided.

United States Patent Stuart 1 Mar. 26, 1974 1 MANDIBULAR MOVEMENT RECORDER [22] Filed: Apr. 2, 1973 [21] Appl. No.: 346,926

Primary Examiner-R0bert Peshock Assistant Examiner-J. Q. Lever Attorney, Agent, or FirmPastoriza & Kelly ABSTRACT The various styli mounted on a lower U shaped frame for making traces on recording plates mounted on an upper U shaped frame in response to movements of a patients mandible when the lower and upper frames are secured to the patients jaws are arranged to be simultaneously retracted from the recording plates by air pressure. Towards this end, an air pressure source feeds a plurality of tubes having exit openings adjacent to the various styli such that an air stream will simultaneously impinge upon surface areas provided on the styli to effect simultaneous retraction. Inadvertent or spurioustraces in retracting the styli as has formerly been done by hand are thus avoided.

4 Claims, 3 Drawing Figures PATENTEDHARZSIBM 3798 77 A R P RESSUR E 500 RCE FIG. 2.

MANDIBULAR MOVEMENT RECORDER This invention relates to an improvement in mandibular movement recorders utilized in dentistry for providing information to be transferred to an articulator in the manufacture of dentures.

BACKGROUND OF THE INVENTION Mandibular movement recorders are well known in the art and function to record the motion of a patients jaws in such a manner that these motions may be subsequently reproduced by an articulator used in the manufacture of properly fitting dentures.

An example of a well known recorder is described and claimed in my US. Pat. No. 2,814,876 issued Dec. 3, 1957 wherein a complete explanation of thefunctioning of the recorder can be found.

Since the motion of the human jaw or mandible involves more than simply a hinging type movement, for example, side movements and forward and backward translational movements referred to as laterotrusion movements, accurate recording of the various movements involves more than one trace or line. Generally, recorders such as set forth in my previous patent include lower and upper frame members arranged to be secured to a patients lower and upper jaws as by bite blocks. The arms of the lower and upper U shapes extend to either side of the patients head, the lower U- shaped frame carrying styli and the upper U-shaped frame carrying recording plates positioned to be engaged by the styli. Movements of the jaw are thus traced by the styli on the recording plates. Normally there are provided three'pairs of recording plates. A first pair includes vertically and horizontally disposed plates with a vertically and horizontally disposed corresponding styli adjacent one side of the patients face and similar vertically and horizontally disposed recording plates and associated vertically and'horizontally disposed styli on the other side of the patients face. The last pair comprise recording plates secured to the central portion of the lower U-shaped frame with styli on the central portion of the upper frame adjacent to the bite blocks for making traces of some of the laterotrusion movements.

After the particular characteristics of a patients jaw movements have been recorded on the plates, the lower and upper U-shaped frames and bite blocks are transferred to a dental articulator and the hinging of the articulator parts are then adjusted to follow the traces established by the recorder so that the articulator then accurately simulates the patients jaw movements. Properly fitting dentures can then be manufactured with the help of the articulator.

In the forming of the various traces by the styli, it is important after themovements to be recorded have been completed that the various styli be lifted from the recording surfaces. This lifting is normally done by hand and since six styli are involved, they cannot easily be simultaneously removed.'As a consequence, inadvertent movements of the patients jaw after perhaps one or two of the styli have been retracted can cause spurious traces to appear on the other recording plates. It would be desirable if the recorder could be provided with some suitable means for retracting or lifting all of the styli simultaneously after the tracings have been completed.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present invention contemplates an improvement to a mandibular movement recorder such as shown and described in my above referred to United States patent. More particularly, this improvement comprises a means for simultaneously lifting all of the various styli from their associated recording plates.

In accord with the improvement, flange means are provided on each of the styli defining surface areas normal to the directions of movement of the styli and air pressure means for directing streams of air simultaneously against the surface areas associated with the flanges on the styli serves to simultaneously retract from the styli from the recording plates after tracings have been completed.

Since most dental laboratories are already provided with a source of air pressure, the present improvement provides a very simple means of effecting a simultaneous retraction of the various styli without having to resort to complicated'electrical or hydraulic means for effecting such retraction and without having to make extensive modifications on the recorder apparatus itself.

BRIEF DESCRIPTION OF THE DRAWINGS A better understanding of the improvement constituting the present invention will be had by now referring to the accompanying drawings in which:

FIG. 1 is a perspective view showing the basic elements of a typical mandibular movement recorder such as shown and described in US. Pat. No. 2,814,876 including the improvement of the present invention;

FIG. 2 is a view partly in cross section taken in the direction of the arrows 22 of FIG. I; I

FIG. 3 is a view similar to FIG. 2 but showing a second position of the styli shown in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION Referring first to FIG. 1 there is shown a typical mandibular movement recorder comprising a U-shaped lower frame including a lower horizontal member 10 supporting a lower bite block 11 at its central portion adapted to be secured to a patients lower teeth so that it moves with movements of the-patients mandible.

The lower member has right and left supporting rods 12 and 13 extending rearwardly so as to assume positions adjacent to the right and left sides of a patients face when the bite block is in position. Right and left vertically and horizontally extending styli 14, 15 and l6, 17, respectively are mounted to end portions of the right and left styli supporting rods 12 and 13 as shown.

A U-shaped upper frame includes an upper horizontal member 18 supporting as at 19 an upper bite block 20 at its central portion adapted to be secured to the patients upper teeth so that it remains in a fixed position relative to the patients head.

The upper member 18 hasright and left recorder plate supporting rods 21 and 22 extending rearwardly so as to be positioned adjacent tothe right and left sides of a patients face when the bite blocks are in position. Right and left vertically and horizontally positioned recording plates 23, 24 and 25, 26 in turn are mounted to the end portions of the right and left recording plate supporting rods 21 and 22 in positions to be engaged by the right and left vertically and horizontally extending styli respectively. In FIG. 1 there are shown pointers 27 and 28 supported by the right and left vertical recording plates 24 and 26 respectively. The purpose for these pointers will become clearer as the description proceeds.

The above described assembly further includes laterotrusion recording styli 29 and 30 mounted on either side of the central portion of the upperhorizontal member 18 for cooperation with recording plates 31 and 32 mounted on either side of the central portion of the lower horizontal member 10.

In accord with the specific improvement of the present invention, the styli include flanges in the form of disks defining surface areas normal to the direction of movement of the styli. These disks or flanges are shown at 33 for the stylus 14, 34 for the stylus 15, 35 for the stylus 16, 36 for the stylus 17, 37 for the stylus 29, and 38 for the stylus 30.

Referring to the lower right hand portion of FIG. 1, there is schematically indicated by the block, an air pressure source 39 having an outlet passing through a manually operable valve 40 to feed air to a plurality of flexible tubes 41, 42, 43, and 44. The flexible tubes 41 and 42 are supported by the U-shaped lower frame while the flexible tubes 43 and 44 are supported on the upper horizontal member 18 of the U-shaped upper frame. These various flexible tubes have a common input end connected to the valve 40 as shown. The outlet ends of the flexible tubes in turn terminate adjacent to the styli in such a manner that upon application of air pressure to the tubes, the output air flow from the output or exit ends of the tubes simultaneously impinges upon the surface areas defined by the various flanges or disks supported by the styli to thereby retract the styli away from their associated recording plates.

The foregoing can better be understood by reference to the fragmentary cross section of FIG. 2 illustrating the exit ends of the flexible tube 42. It will be understood that the exit ends for the flexible tube 41 function in a similar manner so that a detailed description of one will suffice for both. Thus, with reference to FIG. 2 the tube 42 terminates in vertical and horizontally directed nozzles 45 and 46 such that when air exits from these nozzles it will impinge against the flange disk 35 and 36 associated with the styli l6 and 17. As shown, the styli l6 and 17 are respectively mounted for sliding in brackets 47 and 48 secured to the styli support rod 13. The sliding movement takes place toward and away from the associated recordingsurface. In the particular embodiment disclosed, the recording end portions of the styli include magnets 49 and 50, These magnets are attracted by the recording plates 25 and 26 to assure that contact of the stylus point will be maintained when the styli are moved into engagement with the plates.

With respect to the foregoing, it will be evident that the vertically disposed stylus 16 would normally remain in contact with the recording plate 25 because of gravity, the magnet 49 having a weight or mass sufficient for this purpose. However, for the horizontally disposed stylus 17, the magnet 50 assures that continuous engagement will be maintained with the recording plate 26.

The brackets 47 and 48 are made of ferrous material so that when the styli are retracted, they will be held in their retracted position by the magnets engaging the brackets. v

In FIG. 2, the styli are shown in engagement with the recording plates. Upon flow of air from the nozzles 45 and 46 against the disks 35 and 36, the styli will be retracted to the position illustrated in FIG. 3. The magnets 49 and 50 will hold the styli in the retracted position even after cessation of the air pressure from the nozzles.

OPERATION In operation, the various styli are first moved to their retracted positions to be out of engagement with the various recording plates. As described inconjunction with FIGS. 2 and 3, the styli are held in these positions by their associated magnets and mounting brackets.

The bite blocks 11 and 20 are then respectively secured to the lower and upper jaws of a patient as by temporarily cementing them to the patient's teeth. It will be noted that the various styli supporting and recorder plate supporting rods 12, 13 and 21, 22 are coupled to the lower and upper horizontally extending members 10 and 18 as by adjusting blocks wherein the lateral spacing between the rods can be adjusted as well as their rotational position on the supporting horizontal member. In addition, the rearward extent of the rods is adjustable by sliding them forwardly and rearwardly in these coupling blocks.

An initial adjustment of the recording'plate supporting rods 21 and 22 is effected by positioning the pointers 27 and 28 as accurately as possible in co-axial relation with the hinge axis of the patients mandible. Thereafter, the styli supporting rods 12 and 13 are adjusted to position the various styli so that they will engage the associated recording plates at approximately the centers of the recording surfaces. Similar adjustments are made for the laterotrusion styli 29 and 30 and cooperating recording plates 31 and 32 on the upper and lower horizontal members 18 and 10 respectively.

Each stylus is then moved forwardly in its bracket towards the associated recording plate so that engagement is effected. The patient is now instructed to effect various movements of his jaw such as opening and closing as well as sidewise and even rotary motions. Tracings will then be made on the various recording plates defining these movements relative to the hinge axis of the mandible as defined by the positionof the pointers 27 and 28. a

After the tracings have been completed, it is desirable to retract all of the styli simultaneously so as to avoid the possibility of any spurious traces which might occur should a successive manual retraction of the styli be carried out. Towards the foregoing end, the dentist or technician will simply open the air valve 40 to permit air from air pressure source 39 to pass through the various' plurality of tubes and out the exit ends of the tubes to impinge against the surface areas defined by the flanges or disks associated with each of the styli. This air pressure will effect a simultaneous retraction of all of the styli as described in FIG. 3, the magnets associated with the styli then holding them in their retracted position.

After retraction of the styli has been completed, the air pressure source is turned off and the recordingassembly removed from the patients head and transferred to an articulator.

It will be understood that various other adjustments are made in addition to those described but the present invention is not concerned with these other adjustments nor with the adjustments of the articulator and thus these details are not set forth.

From the foregoing description, it will be evident that the present invention has provided a very simply means for effecting a simultaneous retraction of all of the styli. Since an air pressure source is normally available in most dental laboratories and offices, very little auxiliary equipment is required. Further, the only modification of the mandibular movement recorder itself involves the provision of the flanges on the styli to define a surface area against which air may be directed. The flexible tubes for carrying the air pressure can easily and inexpensively be attached to the lower and upper U shaped frames as required.

What is claimed:

1. In a mandibular recorder including lower and upper U-shaped frames secured to the lower and upper jaws of a patient respectively, the end portions of the frame supporting marking styli and recording plates respectively so that traces are made on the plates by the styli upon movement of the patients mandible, the improvement comprising:

a. flange means on the styli defining surface areas normal to the directions of movement of the styli; and,

b. air pressure means for directing streams of air simultaneously against the surface areas associated with the flange means on the styli to simultaneously retract the styli from the recording plates after tracings have been completed.

2. The improvement according to claim 1, in which each stylus is mounted in an associated mounting bracket and includes a magnet connected to the stylus for movement with the stylus, the magnet being attracted to the mounting plate when the stylus is retracted to hold the stylus in a retracted position.

3. An improved mandibular movement recorder, comprising, in combination:

a. a U-shaped lower frame including a lower horizontal member supporting a lower bite block at its central portion adapted to be secured to a patients lower teeth so that it moves with movements of the patients mandible, the lower member having right and left styli recording rods extending rearwardly adjacent to the sides of the patients face;

b. right and left vertically and horizontally extending styli mounted to the end portions of the right and left styli supporting rods, respectively;

c. a U-shaped upper frame including an upper horizontal member supporting an upper bite block at its central portion adapted to be secured to the patients teeth so that it remains in a fixed position relative to the patients head, the upper member having right and left recorder plate supporting rods extending rearwardly adjacent to the right and left sides of the patients face respectively;

d. right and left vertically and horizontally positioned recording plates mounted to the end portions of the right and left recording plate supporting rods respectively, in positions to be engaged by the right and left vertically and horizontally extending styli respectively;

e. laterotrusion recording plates and styli mounted respectively on either side of the central portions of the lower and upper horizontal members respectively, each stylus being slidably mounted in a mounting bracket for movement towards and away from its associated recording plate and each stylus including a flange defining a surface area normal to its direction of movement; and

f. a plurality of flexible tubes supported by the U shaped lower frame having a common input end for connection to a source of air pressure and a plurality of output ends positioned adjacent to the styli supported by the lower U-shaped frame and the upper horizontal member such that upon application of air pressure to the tubes, the output air flow to engage the plate and for holding the stylus in a retracted position by magnetic attraction to its associated mounting bracket when the stylus is moved to its retracted position by said air pressure impinging on the flange surface. 7 

1. In a mandibular recorder including lower and upper U-shaped frames secured to the lower and upper jaws of a patient respectively, the end portions of the frame supporting marking styli and recording plates respectively so that traces are made on the plates by the styli upon movement of the patient''s mandible, the improvement comprising: a. flange means on the styli defining surface areas normal to the directions of movement of the styli; and, b. air pressure means for directing streams of air simultaneously against the surface areas associated with the flange means on the styli to simultaneously retract the styli from the recording plates after tracings have been completed.
 2. The improvemEnt according to claim 1, in which each stylus is mounted in an associated mounting bracket and includes a magnet connected to the stylus for movement with the stylus, the magnet being attracted to the mounting plate when the stylus is retracted to hold the stylus in a retracted position.
 3. An improved mandibular movement recorder, comprising, in combination: a. a U-shaped lower frame including a lower horizontal member supporting a lower bite block at its central portion adapted to be secured to a patient''s lower teeth so that it moves with movements of the patient''s mandible, the lower member having right and left styli recording rods extending rearwardly adjacent to the sides of the patient''s face; b. right and left vertically and horizontally extending styli mounted to the end portions of the right and left styli supporting rods, respectively; c. a U-shaped upper frame including an upper horizontal member supporting an upper bite block at its central portion adapted to be secured to the patient''s teeth so that it remains in a fixed position relative to the patient''s head, the upper member having right and left recorder plate supporting rods extending rearwardly adjacent to the right and left sides of the patient''s face respectively; d. right and left vertically and horizontally positioned recording plates mounted to the end portions of the right and left recording plate supporting rods respectively, in positions to be engaged by the right and left vertically and horizontally extending styli respectively; e. laterotrusion recording plates and styli mounted respectively on either side of the central portions of the lower and upper horizontal members respectively, each stylus being slidably mounted in a mounting bracket for movement towards and away from its associated recording plate and each stylus including a flange defining a surface area normal to its direction of movement; and f. a plurality of flexible tubes supported by the U shaped lower frame having a common input end for connection to a source of air pressure and a plurality of output ends positioned adjacent to the styli supported by the lower U-shaped frame and the upper horizontal member such that upon application of air pressure to the tubes, the output air flow from the exit ends simultaneously impinges upon the surface areas defined by the styli flanges to simultaneously retract the styli away from their associated recording plates, whereby termination of the recording of movements of the patient''s mandible can be effected simultaneously.
 4. An improved recorder according to claim 3, in which each stylus carries a magnet to attract the stylus to its associated recording plate when slidably moved to engage the plate and for holding the stylus in a retracted position by magnetic attraction to its associated mounting bracket when the stylus is moved to its retracted position by said air pressure impinging on the flange surface. 